The disclosure relates to a pin eject system in a rotary cutting die arrangement comprising a rotary die cutting cylinder and an anvil roll with a media passing therebetween. The rotary cutting die arrangement is used in the converting industry to cut parts from a media passing between the two cylinders. The pin eject system facilitates the separation of the cut part from the media.
In one aspect, the disclosure relates to a rotary die cutting cylinder of the rotary die cutting arrangement with an insert removably attached to the outer surface of the rotary die cutting cylinder. The insert receives a pin to provide the pin ejection feature. The insert may be received in a recess formed on the outer surface of the rotary die cutting cylinder and held in position with a mechanical fastener with the pin projecting from the surface of the insert. The insert may also have a die cavity and the ejector pin may project through a hole in the die cavity of the insert. The pin is located within the insert and is biased outward from the outer surface of the rotary die cutting cylinder by a compressible, springing core disposed in the bore of the rotary cutting cylinder. During cutting, the media is compressed, for instance, in a die cavity formed on the face of the insert, and the anvil roll, and cut. The portion of the media in the cavity pushes against the ejector pin and the pin retracts through its hole in the insert against the compressible core. As the insert and die cavity rotate away from the anvil roll, the pin moves outward by the biasing force of the compressible core and ejects the part (or die cut slug) from the cavity. The pin eject system prevents the build-up of small die cut slugs in die cavities of the die.
In another aspect, the disclosure relates to an anvil roll of the rotary die cutting arrangement with an insert and a pin ejection feature that cooperates with a die cavity of a rotary cutting cylinder to maintain the cut media within the die cavity or to separate the media from the cut media within the die cavity. The insert may be received in a recess formed on the outer surface of the anvil roll and held in position with a mechanical fastener with the pin projecting from the surface of the insert. In one example, when the anvil rotates, the insert and pin eject feature of the anvil roll comes into register with die cavity of the rotary cutting cylinder. The pin housed in the insert projects into a cutting die area of the cutting cylinder and is biased outward by a compressible, springing core disposed in the bore of the anvil roll. The ejector pin projects through its hole in the insert in the anvil roll outer surface and comes into register with the die cavity at selected points during cutting. As the media is compressed in the cavity between the rotary cutting cylinder and the anvil roll, and cut, the pins push the material into the die cavity. As another example, inserts with the pins may be provided on other areas of the anvil roll. The pins may project outward from the anvil roll in areas outside of the die cavity during cutting. As the media is compressed in the cavity between the rotary cutting cylinder and the anvil roll, and cut, the pins push the material outside of the die cavity away from the material within the die cavity, thereby facilitating the removal of the die cut portion from the remaining portion of the media outside of the cavity.
More in particular, the disclosure is directed to the insert assembly comprising the insert and pin which facilitates the set-up of a cylinder, and changeover from job to job. The insert assembly, which is removably attachable at the outer surface of the rotatory die cutting cylinder, eliminates the need to install pins through the bore of the cylinder and reduces set-up of the cylinder and increases operational flexibility.